Three section envelope blank



FIG. 1 is a plan view in flat unfolded state, of a three sectionenvelope blank, showing my new design the rear surface which is plain;

FIG. 2 is a plan view of a modification thereof in which sections forprinted matter are shown in a portion thereof;

FIG. 3 is a perspective view of the three section envelope blank in apartial stage of folding thereof; and

FIG. 4 is a perspective view of the completely folded three sectionenvelope blank.

The ornamental design for a three section envelope blank, as shown anddescribed.